Drawing ring for wire-drawing machines



Oct. 16, 1928.

Filed Jan. 11, 1928 ATTa/Pn/ Patented Oct. 16, 1928.

UNITED STATES PATENT OFFICE.

PETER DARMSTADT, WILHELM STEGMANN, AND VALENTIN WEIIJ, FECHENHEIM,

NEAR FRANKFORT-ON-THE-MAIN, GERMANY, ASSIGNORS TO THE FIR-M DRAHT-INDUSTRIE PETER DARMSTADT A6v CO., G. M. B. H., OF FRANKFORT-ON-THEMAIN,

GERMANY.

Application mea January 11, 192s, serial No.

It is well known to provide the rotating drawing rolls or rollers ofwire drawing machines with separate drawing rings loosely vfittedthereon which feed the wire by reason of the friction between the ringand the drawing roll or roller, and are adapted to compensate for thelengthening which o ccurs durv drawing rings hitherto used for thispurpose were of comparatively large cross section and were rigid.Consequently the' friction between the ring and the drawing roll orroller was too low'and attempts were made to increase this bylubricating the'contact surfaces* witha suitable adhesive (lubricant ofgreat*v toughness). This method fulfills its purpose when the speed ofdrawing` is not too high, but has not been found very satisfactory. .Inconsequence of the increase indrawing speed which it .has been attemptedto obtainoin recent times, particularly for the purpose of `greatereconomy, the drawing'members are considerably heated, that is to say therotary drawing rolls or rollers and the loosely fitted drawing ring, sothat the lubricant is rendered fluid to such` an Iextent that it is ynolongervpossible forthedrawing rings to op erate properly at high drawingspeeds. v

According to the invention thereare used for the purpose ofincreasingthe friction Ibetween the drawing rings and the drawing rollsor rollers, elastic drawing rings, that is to say thecross section ofthese rings is so 40 dimensioned that during the drawing operation theyare capable of being'deformed under the action of the .pulling tensionof the wire and consequently the surface with which they bear againstthe drawing rolls or rollers .45 is increased.

In the accompanying drawing are illus- DRAWING RING FOR WIRE-DRAWINGMACHINES.

245,835, and in Germany September 22, 1927.

In order that the invention may be readily l understood the proportionshave been-exaggerated in the drawing. v

The drawing ring c, according to the invention, is made deformable andelast-ic, and` in the normal or unstrained :condition (Figure l) bearsonly with a small contact'.

surface on its drawing roll or roller b. As soon, however, as it comesunder the action of the variable pulling tension of the wire to bedrawn, it is deformed and the contact or bearing surface becomes largerin proportion to the increase of the pulling tension of the wire(Figure2) and Aconsequently the frici tion between the drawing ring andthe drawing roll or roller is proportionatelyincreased. By means of thenew elastic drawing rings, whilst avoiding any separate adhesivelubrieating means, the object of the frictional drive and the feeding ofthe wire is effected in a simple and very effective manner whilstconstantly vcompensating for increases in length, even at high drawingspeeds.

On the periphery the rings may be provided with one or more ribs servingas guide tracks or paths for ythe wirepassed over them.

At high drawing speeds they also preventthe undesirable cuttlng actionof the wire as also` the breakage thereof which frequently occurs withthe constructions used hitherto.

We wish it to be understood that the illustrationsin the drawings arediagrammatic only land thatvarious refinements may be made within thescope ofthe appended claim. A continuous ring has been shown freelyfitted upon a driving roll. By continuous ring we mean a ring that hasno gaps or open cross-cut spaces in its periphery, and during thedrawing operation-to vary the by freely fitted We refer only to a ringWhose area of the bearing surface between the ring rotation about thedrum is unlimited. and the roller in accordance with Variations Weclaim: in the tension of the wire. 6 In combination. with a drawingroller of In witness whereof we have hereunto set l5 a Wire-drawingmachine, an elastic continuour hands.` t ous ring fitted freelyon suchroller, said ring being adapted to Contact with the Wire along PETERDARMSTADT. only a ortion of its periphery, the ring thus W'ILHELMSTEGMANN. 10 being eformable by the tension of the wire VALENTIN WEIL.

